A former leading fund-raiser for Sen. Hillary Clinton (D-NY) has joined Barack Obama’s (D-Il) National Finance Committee and committed to playing what he describes as a "significant fund-raising role for (Obama’s) campaign both here in New Jersey and across the country."

Michael Kempner, one of Clinton’s national finance co-chairs during her failed presidential bid and a member of "The Group," today plans to send a letter to friends and fellow Democrats indicating his support for Obama, and welcoming them to join him in the general election campaign against presumptive GOP presidential nominee Sen. John McCain (D-AZ).

"After meeting on several occasions with Hillary and Senator Obama over the past few weeks, I have come to the conclusion that we must elect Senator Obama as our next President," Kempner wrote in a draft letter he shared with PolitickerNJ.com.

"In Barack Obama I have found a person who is extraordinarily comfortable with who he is, someone genuinely warm and welcoming and most importantly, someone with an impressive inner strength," wrote Kempner, president and CEO of MWW, one of the state’s top public relations firms.

"While I may not agree with him (or Hillary Clinton) on every issue, he has the intelligence and conviction to work for positive change...and has the potential to be a transformative figure in American politics," he added.

After playing an important role for 17 months in Clinton’s inner fund-raising circle, Kempner admitted that he ended the campaign "bitter and angry by how Hillary was treated by the media, DNC Chair Howard Dean, Speaker Nancy Pelosi and the Democratic Party establishment."

His decision to back Obama was painful.

But after several weeks and the ensuing addition of many Clinton advisors to Obama’s staff and inner circle, "I have seen a softening of rhetoric and the adoption of policies that are more in line with my views and that of many of my friends," said Kempner.